Synthesis and Fungicidal Activities of Benzofuran‐Substitutes Cinnamamide Compounds

Abstract The commercially available dimethomorph is a mixture of two isomers, among which Z‐ dimethomorph has an excellent control effect against oomycetes, while E‐dimethomorph has less fungicidal activity. Therefore, in this paper, a series of novel benzofuran‐modified cinnamamide derivatives were designed and synthesized by “fixing” the cis‐styrene group in Z‐dimethomorph with benzofuran group. And the modification of the molecular structure of cinnamamide compounds could be beneficial to improve its practical application performance. The synthesized products were evaluated for their antifungal activity against 7 strains of phytopathogenic fungi. It was found that the antifungal spectrum and fungicidal activities of some compounds were improved compared with the commercial fungicides dimethomorph and flumorph. Furthermore, for benzofuran‐modified cinnamamide derivatives, substituted bis ‐methoxy in the phenyl ring of cinnamate is crucial to inhibit Phytophthora infestans and Phytophthora dreschsleri .